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Dear Editors,

We appreciate your comments on our paper, in which you suggested alternatives to the enzymatic stromal vascular fraction (SVF) and safety issues. We were very interested in your opinions.

Your first comment was on the usage of type II collagenase. This enzyme is used widely for the enzymatic digestion of centrifuged fat, as it dissociates adipose cell membranes most efficiently. However, to extract stem cells from adipose tissue, it is more useful to digest the collagen rather than the adipose cell membrane. As the substrates of type II collagenase are collagen types I, III, V, VII, VIII, and X, fibronectin, gelatin, and aggrecan, this enzyme has a better harvesting effect on cells from dermal and fat tissue....

Notes

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All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards.

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Additional informed consent was obtained from all individual participants for whom identifying information is included in this article.

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